Electric Skateboard Basics: Batteries
Batteries is one of the most important components to electric skateboard, which is closely related to the speed and range. It’s also the most dangerous parts. It could lead to battery bursting due to improper use or poor quality. So for the sake of the skater’s safety, it’s essential to know a bit more about batteries. Let’s get started.
Main battery terms
For newcomers to electric skateboard community, trying to understand the batteries can be an overwhelming experience. Before we discuss different parameters or brands, there are some terms about batteries you need to know.
Voltage (V): The torque that a board gives. Also improves the efficiency of the battery range. If the voltage is too low, the board will not have enough torque. If the voltage is too high, the motor/ ESC can not handle it.
Industry standard = 36V.
Ampere (A): The current that a battery can give. This affects the top speed.
Continuous discharge current: The ampere that the battery can provide continuously without overheating. Most electric skateboards need their batteries to be at least 30A continuous.
Ampere Hours (Ah): The charge that a battery holds (Number of Ampere that a battery can put out if it was to fully discharge in one hour). This affects the range.
1000mAH = 1Ah
Watt Hours (Wh): The power that a battery can output in one hour. Watt Hours is the total battery size and an even better indicator of range.
Wh = Ah * max voltage
General rule of thumb is Watt Hours/ 10=Range(in km) .
Main battery qualities
It’s not easy to choose a battery while you’re looking for because there are a lot options there. And you can’t just use some old battery and expect your board function properly. There are a few things you have to look for and a few qualities in batteries that need to exist for your board to work to the fullest. Three main qualities of electric skateboard battery is high amp output and high discharge rate, proper voltage, and proper capacity. Without capacity, you’re not going very far. Without voltage, you’re not going very fast. Without good output, you’re not going anywhere at all. So you need to take these three things into consideration when you’re looking for a battery. Now let’s take a look at those qualities.
Let’s start with high amp output and high discharge rate. What does that actually mean? Well, when you’re looking for electric skateboard you want to look for a battery that has at least a 30 amp output. And you cannot use a simple power bank to try to run your electric skateboard. Those battery packs of power bank are designed to only output 1 or 2 amps to charge your smart phone, not 30 for electric skateboard. Using those battery packs even at 3, 4 or 5 amps would damage it. So keep in mind that you need a very specific battery for electric skateboard. Just because it has a really big capacity does not mean it’s going to work for you.
Proper voltage is super important. Voltage directly impacts your speed. Any cells in series make the voltage higher which increases your speed. Any cells in parallel increase the capacity and discharge rate. Please be noted that here in the passage, letter “s” means cells in series, and letter “p” refers to cells in parallel. 6s is the absolute bottom. It’s more of a slower board. That’s 16 to 18 miles per hour top speed, while 12s is like 30 to 35 miles per hour, which would be a little too fast. So for most people, 10s is a nice option and it’s about 25 miles per hour.
After high amp output and proper voltage, you need an adequate capacity. Without capacity, you’re not going very far. Nobody wants to ride a electric skateboard for two minutes and then you have to charge it again. Typically looking at the milliamp power ratings of batteries isn’t the most accurate way of determining your range. Batteries with about 5000 milliamp hours at the least are recommended. Any batteries more than that is just a bonus. While looking for batteries, keep an eye on the milliamp power rating but also look at the watt hour rating. Watt hour rating will be way more accurate when it comes to figure out your range. For example, 180 watt hours is about 10 miles of range. Of course, you still need to consider lots of other factors. It depends on your wheel size, what motor you’re using, the weight of the rider, which ESC you’re using, the efficiency of your whole build. The higher the watt hour rating is, the more range you will have. So just find that data when you’re looking for batteries and keep the data as high as you can.
Main battery types
Electric skateboards draw a ton of power. To put that into perspective, it needs a battery that can supply the power that the ESC and the motor are asking for. There are tons of different types of batteries and different chemistry out there, but there are mainly two batteries that most of us stick to. That is lithium ion batteries and lithium polymer batteries. These two types of batteries are relatively light and high-powered. There are a number of characteristics that are unique to each category.
Li-Ion (Lithium Ion) batteries are made up of three components and that is an anode, an electrolyte and a cathode. When the battery is charged, the anode is charged with lithium ions (this is called intercalation). As the battery discharges, the ions move from the anode over to the cathode through the electrolyte (this is called de-intercalation). Most lithium-ion batteries, unlike more traditional ones, also include an electronic controller, which regulates power and discharge flows so your battery doesn’t overheat or explode. Li-ion battery packs usually already come with a BMS installed and are more plug-and-play. You just plug the charger into the charge board and you’re good to go.
Li-Po (Lithium Polymer) batteries are cheaper and have less voltage sag. However, there are some disadvantages of this battery type that limits its use in commercial boards. First they’re less safe and could start a fire if not handled properly, and nobody wants to see that and no companies want to take the consequences of exploding. Besides, for Li-Po batteries, usually you need to either install BMS (battery management system) yourself or you need to get a balance charger to balance charge them properly. You have to charge each battery pack separately which can be kind of pain. On top of that, Li-Po batteries get old kind of quickly, so they have a shorter life-cycle compared to Li-ion battery.
The most significant difference between lithium-ion and lithium-polymer batteries is the chemical electrolyte between their positive and negative electrodes. In Li-Po batteries it isn’t a liquid. Instead, Li-Po technology uses one of three forms: a dry solid, a porous chemical compound or a gel-like electrolyte. The most popular among these is the last one. But there is a common misconception. Plenty of manufacturers are not actually selling you a true Li-Po battery, instead it’s a Li-ion battery in a poly casing. No matter what batteries you choose, the only that mat matters is the chemistry of the battery. Choosing the battery that fits your needs for the drain requirements. The container that the battery comes in, if it’s a flat pack or a cell, it doesn’t matter.
Why is it cheaper? Well, that’s because it’s based on standardized format. 18650 batteries are 18mm wide and 65mm tall. Batteries also come in 17500, 17670, 18350, 18490, 18500. However, the most commonly used size and agreed-on dimension is 18650. This is why they are used in almost everything. That means they are used in laptops, flashlights, cameras, all kinds of electronics and even power tools. The difference is that usually when you buy a device that has 18650 batteries in it it’s arranged into a pack and surrounded with a plastic casing. And inside the pack, if the manufacturer is good, they also include a protection circuit and a BMS. This is the safest way to use 18650 batteries in a high drain device.
A rechargeable battery is a type of electrical battery which can be charged, discharged into a load, and recharged many times, as opposed to a disposable or primary battery, which is supplied fully charged and discarded after use. It is composed of one or more electrochemical cells. Rechargeable batteries are produced in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network. Several different combinations of electrode materials and electrolytes are used, including lead-acid, nickel- cadmium, nickel-metal hydride, lithium-ion, and lithium-ion polymer. Rechargeable batteries typically initially cost more than disposable batteries, but have a much lower total cost of ownership and environmental impact, as they can be recharged inexpensively many times before they need replacing.
Like always, the best electric skateboard parts are the ones that you can afford, but with batteries be really careful. Don’t buy something too cheap. If it’s too good to be true, it’s probably is. Don’t buy fake batteries. Spend a little bit more on your battery and maybe you can find other ways to save on the rest of the electric skateboard parts. So what batteries are you thinking about getting? What configuration are you gonna use? Let us know in the comments. We’d love to hear what your thoughts are. If you have any questions, drop them in the comments below. We’re always around to answer your questions.